This invention relates to sealing the anus of carcasses of slaughtered animals, e.g. sheep, cattle, calves, pigs, and other species.
A number of different systems are known for sealing the anus of the carcass of a slaughtered animal. For smaller animals such as sheep and calves, it is known to provide one piece internal plugs made from plastics material, recycled paper, and the like. These plums are inserted through the anus into the rectum. One shortcoming of this type of system is that the natural elasticity of the rectum allows faecal material to move past or to dislodge these internal plugs, so that they are ineffective in preventing contamination of the carcass. Another limitation of this type of prior system is that an abattoir worker needs to manually grasp the anus and to cut around the rectum to enable the plugged rectum to be removed along with other abdominal viscera. This grasping and cutting operation can lead to contamination of the worker""s hands and can increase the risk of the worker contracting some disease or being injured.
Another known system, particularly for cattle, called xe2x80x9cbagging the anusxe2x80x9d involves applying a plastic bag or the like over the end section of the rectum thereby enclosing the anus, the plastic bag being held in position with an elastic ring or the like tightly clamping the plastic bag around the rectum. This system has been used in manual anus sealing operations and also in mechanised or semi-automatic systems such as the one described in international patent application No. PCT/AU95/00637 (publication No. WO-96/09770). Bagging of the anus can be unsuitable where the time available for the operations on each carcass is too short to perform all the necessary operations to complete the bagging. Another drawback of this system is the unwanted introduction of polyethylene in the rendered tallow.
It is an object of the present invention to provide a process for effectively sealing the anus of the carcass of a slaughtered animal prior to subsequent processing.
It is a further object of the present invention to provide an anal seal for sealing the anus of a carcass of a slaughtered animal in an effective manner prior to subsequent processing of the carcass.
It is a further and preferred object to provide an anal seal which can minimise or prevent faecal contamination of the hands of an abattoir worker, can reduce the risk of contracting disease and can assist with the operation of cutting the rectum free of the carcass.
According to the present invention there is provided a process for sealing the anus of the carcass of a slaughtered animal, the process including the steps of clearing the hide, skin or pelt from the immediate vicinity of the anus, leaving the anal sphincter substantially intact, inserting a plug through the anus and into the rectum of the carcass of the slaughtered animal to a depth such that the sphincter muscle contracts behind and around the periphery of a back end of the plug, clamping the sphincter muscle by moving a clamp associated with the plug into a clamping position in which it engages with the sphincter muscle that has contracted behind the back end of the plug so as to clamp the sphincter muscle between the plug and the clamp, and holding the clamp in its clamping position so that the anus is sealed prior to subsequent processing of the carcass.
In the preferred embodiment the plug is provided with a stem extending out from the back end of the plug, and the clamp includes a clamping member which is slidably movable along the stem and is moved along the stem to clamp the anal sphincter against the back end of the plug. After clamping of the sphincter muscle is effected, the stem may be pulled in the caudal direction relative to the carcass to thereby apply tension to the rectum, the tensioning of the rectum being followed by the step of cutting tissues around the rectum to separate it, without puncturing or piercing the rectum, to the desired depth into the pelvic cavity of the carcass. Cutting around the rectum may be carried out by a cylindrical cutting device having a leading cutting edge and a diameter chosen to cut through the tissues surrounding the rectum but without cutting into the rectum, the cutting around the rectum being carried out by relatively advancing the cutting device while the rectum is relatively drawn in the caudal direction concentrically through the cutting device.
After the anus has been sealed and the rectum has been cut from surrounding tissues so that it is cut free from the carcass, the rectum with the anal seal remaining attached may be pulled through the pelvic canal and into the body cavity of the carcass during an evisceration process, followed by removing the rectum together with the viscera with the anal seal still in place and effectively sealing the anus, and subsequently releasing the anal seal and recovering it prior to further processing of the viscera.
According to the present invention there is also provided an anal seal for sealing the anus of the carcass of a slaughtered animal, the anal seal including a plug for insertion through the anus and into the rectum of the carcass of the slaughtered animal so that tissues contract behind the plug, a clamp associated with the plug and arranged for movement towards the plus to a clamping position in which it engages with tissues that have contracted behind the plug so as to clamp the tissues between the plug and the clamp, and retaining means to hold the clamp in its clamping position so that the anus is sealed prior to subsequent processing of the carcass.